Improve selector suggestions

[LinqLover]

Two related issues:

1. When typing something like Transcript showln: #completio, symbols (here: #completion) are not suggested, but only class names.

2. When typing something like 123<linebreak>#compareSafel, #compareSafely: is suggested correctly, but expanding it inserts placeholders for the arguments (___) even though the symbol was meant to be entered as a symbol indeed.

   (This example may also reveal another usage problem: In this example, I am taking notes in a syntax-highlighting workspace and actually would not expect to continue the expression from the first line in the second line - but unfortunately, this is how Smalltalk works ...) Anyway, I think when the symbol is prefixed with a hash, it should actually also be completed as a symbol.

Wdyt? As far as it concerns my personal usage, this area might be one of my (probably: the) most annoying behavior when working Autocompletion which I otherwise find great :-)